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<div class="refentry">
<a name="boost.units.static_rational"></a><div class="titlepage"></div>
<div class="refnamediv">
<h2><span class="refentrytitle">Class template static_rational</span></h2>
<p>boost::units::static_rational</p>
</div>
<h2 class="refsynopsisdiv-title">Synopsis</h2>
<div class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../../boost_units/Reference.html#header.boost.units.static_rational_hpp" title="Header &lt;boost/units/static_rational.hpp&gt;">boost/units/static_rational.hpp</a>&gt;

</span><span class="keyword">template</span><span class="special">&lt;</span><span class="identifier">integer_type</span> N<span class="special">,</span> <span class="identifier">integer_type</span> D <span class="special">=</span> <span class="number">1</span><span class="special">&gt;</span> 
<span class="keyword">class</span> <a class="link" href="static_rational.html" title="Class template static_rational">static_rational</a> <span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
  <span class="comment">// types</span>
  <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span>                               <a name="boost.units.static_rational.tag"></a><span class="identifier">tag</span><span class="special">;</span> 
  <span class="keyword">typedef</span> <a class="link" href="static_rational.html" title="Class template static_rational">static_rational</a><span class="special">&lt;</span> <span class="identifier">Numerator</span><span class="special">,</span> <span class="identifier">Denominator</span> <span class="special">&gt;</span> <a name="boost.units.static_rational.type"></a><span class="identifier">type</span><span class="special">;</span>  <span class="comment">// static_rational&lt;N,D&gt; reduced by GCD </span>

  <span class="comment">// <a class="link" href="static_rational.html#boost.units.static_rationalconstruct-copy-destruct">construct/copy/destruct</a></span>
  <a class="link" href="static_rational.html#id-1_3_43_10_2_41_2_1_2_9-bb"><span class="identifier">static_rational</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>

  <span class="comment">// <a class="link" href="static_rational.html#id-1_3_43_10_2_41_2_1_2_7-bb">public static functions</a></span>
  <span class="keyword">static</span> <span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">integer_type</span> <a class="link" href="static_rational.html#id-1_3_43_10_2_41_2_1_2_7_1-bb"><span class="identifier">numerator</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">static</span> <span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">integer_type</span> <a class="link" href="static_rational.html#id-1_3_43_10_2_41_2_1_2_7_2-bb"><span class="identifier">denominator</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>

  <span class="comment">// public data members</span>
  <span class="identifier">BOOST_STATIC_CONSTEXPR</span> <span class="identifier">integer_type</span> <span class="identifier">Numerator</span><span class="special">;</span>
  <span class="identifier">BOOST_STATIC_CONSTEXPR</span> <span class="identifier">integer_type</span> <span class="identifier">Denominator</span><span class="special">;</span>
<span class="special">}</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="id-1.3.43.10.2.41.5.4"></a><h2>Description</h2>
<p>This is an implementation of a compile time rational number, where <code class="computeroutput">static_rational&lt;N,D&gt;</code> represents a rational number with numerator <code class="computeroutput">N</code> and denominator <code class="computeroutput">D</code>. Because of the potential for ambiguity arising from multiple equivalent values of <code class="computeroutput"><a class="link" href="static_rational.html" title="Class template static_rational">static_rational</a></code> (e.g. <code class="computeroutput">static_rational&lt;6,2&gt;==static_rational&lt;3&gt;</code>), static rationals should always be accessed through <code class="computeroutput">static_rational&lt;N,D&gt;::type</code>. Template specialization prevents instantiation of zero denominators (i.e. <code class="computeroutput">static_rational&lt;N,0&gt;</code>). The following compile-time arithmetic operators are provided for <a class="link" href="static_rational.html" title="Class template static_rational">static_rational</a> variables only (no operators are defined between long and <a class="link" href="static_rational.html" title="Class template static_rational">static_rational</a>):</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p><code class="computeroutput">mpl::negate</code> </p></li>
<li class="listitem"><p><code class="computeroutput">mpl::plus</code> </p></li>
<li class="listitem"><p><code class="computeroutput">mpl::minus</code> </p></li>
<li class="listitem"><p><code class="computeroutput">mpl::times</code> </p></li>
<li class="listitem"><p><code class="computeroutput">mpl::divides</code> </p></li>
</ul></div>
<p>
</p>
<p>Neither <code class="computeroutput"><a class="link" href="static_power.html" title="Struct template static_power">static_power</a></code> nor <code class="computeroutput"><a class="link" href="static_root.html" title="Struct template static_root">static_root</a></code> are defined for <code class="computeroutput"><a class="link" href="static_rational.html" title="Class template static_rational">static_rational</a></code>. This is because template types may not be floating point values, while powers and roots of rational numbers can produce floating point values. </p>
<div class="refsect2">
<a name="id-1.3.43.10.2.41.5.4.4"></a><h3>
<a name="boost.units.static_rationalconstruct-copy-destruct"></a><code class="computeroutput">static_rational</code> 
        public
       construct/copy/destruct</h3>
<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><pre class="literallayout"><a name="id-1_3_43_10_2_41_2_1_2_9-bb"></a><span class="identifier">static_rational</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre></li></ol></div>
</div>
<div class="refsect2">
<a name="id-1.3.43.10.2.41.5.4.5"></a><h3>
<a name="id-1_3_43_10_2_41_2_1_2_7-bb"></a><code class="computeroutput">static_rational</code> public static functions</h3>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem"><pre class="literallayout"><span class="keyword">static</span> <span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">integer_type</span> <a name="id-1_3_43_10_2_41_2_1_2_7_1-bb"></a><span class="identifier">numerator</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre></li>
<li class="listitem"><pre class="literallayout"><span class="keyword">static</span> <span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">integer_type</span> <a name="id-1_3_43_10_2_41_2_1_2_7_2-bb"></a><span class="identifier">denominator</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre></li>
</ol></div>
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<div class="copyright-footer">Copyright © 2003-2008 Matthias Christian Schabel<br>Copyright © 2007-2010 Steven
      Watanabe<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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